Active gas generation apparatus

An active gas generation apparatus configured to generate an active gas by activating a source gas supplied to a discharge space, the active gas generation apparatus comprising:

• a housing configured to house an electrode structure in an in-housing space, the housing having conductivity;
• and
• the electrode structure disposed on a bottom surface of the housing,
• wherein the housing has a bottom surface structure including a flat surface and a buffer space recessed in a depth direction from the flat surface, and the electrode structure is disposed to close the buffer space,
• wherein the electrode structure includes:
• a first electrode component, and
• a second electrode component provided below the first electrode component,
• wherein the first electrode component includes a first electrode dielectric film and a first electrode conductive film formed on an upper surface of the first electrode dielectric film,
• wherein the second electrode component includes a second electrode dielectric film and a second electrode conductive film formed on a lower surface of the second electrode dielectric film, and the second electrode conductive film and the flat surface of the housing are in contact with each other,
• wherein the second electrode dielectric film has a dielectric through hole penetrating the second electrode dielectric film in a region overlapping the buffer space in a plan view, the second electrode conductive film has a conductive film opening in a region overlapping the buffer space in a plan view, the conductive film opening overlaps the dielectric through hole in a plan view, and an outer circumferential line of the conductive film opening is defined as an electrode boundary line,
• wherein the second electrode component further includes a cover dielectric film covering the electrode boundary line of the second electrode conductive film in the buffer space, and the cover dielectric film has a cover through hole penetrating the cover dielectric film in a region overlapping the dielectric through hole in a plan view,
• the active gas generation apparatus further comprising:
• a shield dielectric film provided in a region overlapping the dielectric through hole and the cover through hole in a plan view on a bottom surface of the buffer space, and
• a gas ejection port provided to penetrate a bottom surface of the buffer space in a peripheral region of the shield dielectric film,
• wherein the gas ejection port overlaps the cover dielectric film in a plan view, and does not overlap the dielectric through hole nor the cover through hole in a plan view,
• wherein an AC voltage is applied to the first electrode conductive film, and the second electrode conductive film is set to a reference potential through the housing,
• wherein a space in which the first electrode dielectric film and the second electrode dielectric film face each other is defined as a main dielectric space, and a space in which the first electrode dielectric film and the shield dielectric film face each other is defined as an auxiliary dielectric space,
• wherein a region where the first and second electrode conductive films overlap in a plan view in the main dielectric space is defined as a main discharge space, a region including the dielectric through hole and the cover through hole in the auxiliary dielectric space is defined as an auxiliary discharge space, and the auxiliary discharge space includes a part of the buffer space above the shield dielectric film,
• wherein the discharge space includes the main discharge space and the auxiliary discharge space, and
• wherein a path leading from the auxiliary discharge space to the gas ejection port is defined as an active gas flow path.